# Riposte: An Anonymous Messaging System Handling Millions of Users

arXiv: https://arxiv.org/abs/1503.06115 · HTML: https://mlsanity.com/paper/1503.06115/

## Key facts

- Cited by 4 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 20 Mar 2015.

## Built on by (most cited first, 4 of 4)

- [GPU-based Private Information Retrieval for On-Device Machine Learning Inference](https://mlsanity.com/paper/2301.10904/) (2023)
- [How to Securely Shuffle? A survey about Secure Shufflers for privacy-preserving computations](https://mlsanity.com/paper/2507.01487/) (2025)
- [IntraShuffler: A Privacy Preserving Framework for Heterogeneous DP Federated Learning](https://mlsanity.com/paper/2606.02563/) (2026)
- [Plausible Deniability Guarantees for Whistleblowers](https://mlsanity.com/paper/2607.13928/) (2026)

## Abstract (arXiv)

This paper presents Riposte, a new system for anonymous broadcast messaging. Riposte is the first such system, to our knowledge, that simultaneously protects against traffic-analysis attacks, prevents anonymous denial-of-service by malicious clients, and scales to million-user anonymity sets. To achieve these properties, Riposte makes novel use of techniques used in systems for private information retrieval and secure multi-party computation. For latency-tolerant workloads with many more readers than writers (e.g. Twitter, Wikileaks), we demonstrate that a three-server Riposte cluster can build an anonymity set of 2,895,216 users in 32 hours.